Don't own the buffer in object::Binary.

Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.

Keeping this ownership would make supporting IR inside native objects
particularly painful.

This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.

This patch introduces a few new types.

* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
  This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
  for convenience functions that take a filename and return both the
  buffer and the Binary using that buffer.

The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216002 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 16 insertions, 8 deletions

diff --git a/tools/llvm-symbolizer/LLVMSymbolize.cpp b/tools/llvm-symbolizer/LLVMSymbolize.cpp
index 14e193a5373..2606beac17b 100644
--- a/tools/llvm-symbolizer/LLVMSymbolize.cpp
+++ b/tools/llvm-symbolizer/LLVMSymbolize.cpp
@@ -300,12 +300,12 @@ LLVMSymbolizer::getOrCreateBinary(const std::string &Path) {
     return I->second;
   Binary *Bin = nullptr;
   Binary *DbgBin = nullptr;
-  ErrorOr<std::unique_ptr<Binary>> BinaryOrErr = createBinary(Path);
+  ErrorOr<OwningBinary<Binary>> BinaryOrErr = createBinary(Path);
   if (!error(BinaryOrErr.getError())) {
-    std::unique_ptr<Binary> &ParsedBinary = BinaryOrErr.get();
+    OwningBinary<Binary> &ParsedBinary = BinaryOrErr.get();
     // Check if it's a universal binary.
-    Bin = ParsedBinary.get();
-    ParsedBinariesAndObjects.push_back(std::move(ParsedBinary));
+    Bin = ParsedBinary.getBinary().get();
+    addOwningBinary(std::move(ParsedBinary));
     if (Bin->isMachO() || Bin->isMachOUniversalBinary()) {
       // On Darwin we may find DWARF in separate object file in
       // resource directory.
@@ -314,8 +314,9 @@ LLVMSymbolizer::getOrCreateBinary(const std::string &Path) {
       BinaryOrErr = createBinary(ResourcePath);
       std::error_code EC = BinaryOrErr.getError();
       if (EC != errc::no_such_file_or_directory && !error(EC)) {
-        DbgBin = BinaryOrErr.get().get();
-        ParsedBinariesAndObjects.push_back(std::move(BinaryOrErr.get()));
+        OwningBinary<Binary> B = std::move(BinaryOrErr.get());
+        DbgBin = B.getBinary().get();
+        addOwningBinary(std::move(B));
       }
     }
     // Try to locate the debug binary using .gnu_debuglink section.
@@ -327,8 +328,9 @@ LLVMSymbolizer::getOrCreateBinary(const std::string &Path) {
           findDebugBinary(Path, DebuglinkName, CRCHash, DebugBinaryPath)) {
         BinaryOrErr = createBinary(DebugBinaryPath);
         if (!error(BinaryOrErr.getError())) {
-          DbgBin = BinaryOrErr.get().get();
-          ParsedBinariesAndObjects.push_back(std::move(BinaryOrErr.get()));
+          OwningBinary<Binary> B = std::move(BinaryOrErr.get());
+          DbgBin = B.getBinary().get();
+          addOwningBinary(std::move(B));
         }
       }
     }
diff --git a/tools/llvm-symbolizer/LLVMSymbolize.h b/tools/llvm-symbolizer/LLVMSymbolize.h
index cd11e656e79..a56f1329fd6 100644
--- a/tools/llvm-symbolizer/LLVMSymbolize.h
+++ b/tools/llvm-symbolizer/LLVMSymbolize.h
@@ -75,6 +75,12 @@ private:
 
   // Owns all the parsed binaries and object files.
   SmallVector<std::unique_ptr<Binary>, 4> ParsedBinariesAndObjects;
+  SmallVector<std::unique_ptr<MemoryBuffer>, 4> MemoryBuffers;
+  void addOwningBinary(OwningBinary<Binary> Bin) {
+    ParsedBinariesAndObjects.push_back(std::move(Bin.getBinary()));
+    MemoryBuffers.push_back(std::move(Bin.getBuffer()));
+  }
+
   // Owns module info objects.
   typedef std::map<std::string, ModuleInfo *> ModuleMapTy;
   ModuleMapTy Modules;